Western Michigan University Radiation Safety Instrumentation and Dosimetry Program I. Purpose A. To provide the means of monitoring exposure and exposure rates to ensure exposure at or from Western Michigan University is As Low As Reasonably Achievable (ALARA). B. To ensure instruments used to assess the radiological conditions are reliable, quality controlled, and available to maintain exposure ALARA and protect the public. i. Instrumentation and Dosimetry Program Rev. 2, 07/04/07 Table of Contents Section Title Page I. Purpose i. II. Definitions 2 III. Responsibilities 2 IV. Requirements for Instrumentation A. Multi-purpose Instruments 3 B. Single-purpose Instruments 3 C. Calibration 4 D. Pre-operational Checks 4 V. Requirements for Dosimetry A. Personal Monitoring Devices Shall Be Issued 5 B. WMU Will Use A Certified Supplier To Provide Dosimetry Services 5 C. Devices Worn For Establishing Record Dose Will Be Processed, Read, And Reported 5 D. Table of Dose Limits 5 E. Process For Conducting The Quarterly Dosimetry Change Out. 6 F. Records and Reports 6 VI. Final Conditions 7 Appendix A. Ludlum Model 3 8 B. Ludlum Model 14 C 11 C. Ludlum Model 14 B 14 D. Ludlum Model 12 Neutron Counter 16 E. Ludlum Model 21 Alpha Counter 18 F. Packard Scintillation Counter 21 Page 1 of 22 Instrumentation and Dosimetry Program Rev. 2, 07/04/07 II. Definitions 'As Found' The readings taken when the instrument is exposed to a known dose Data rate prior to calibration adjustments. Calibration The determination of variation or accuracy from a standard of a measuring instrument to ascertain necessary correction factors. ccpm Stands for corrected counts per minute. It is derived from subtracted the background reading (cpm) from the sample or survey reading (cpm) when determining loose or fixed contamination levels. Conversion rule Mathematical formula based on calibration data that converts the instrument readings from cpm to dose rate readings in mR/hr. Declared A woman that has voluntarily informed the RSO, in writing, of her pregnant pregnancy and estimated date of conception. women Dose A general term that refers to absorbed dose or dose equivalent. Exposure The act of being exposed to ionizing radiation or radioactive material. Extremities The parts of the arms from the elbow to the fingertips and the legs from the knees to the toes. Multi-purpose These instruments are built with a meter face that can be read in cpm instruments or mR/hr. The multi-purpose instruments are calibrated in the count rate mode (cpm) on the x 0.1 scale and in the dose rate mode (mR/Hr) for the other scales. Occupational The dose received in the course of employment in which duties exposure involve exposure to ionizing radiation. Personal A device such as a film badge or pocket dosimeter designed to be monitoring worn or carried by the individual for estimating the dose received. devices Pre-operational A series of instrument checks that verify that the instrument can checks reproduce accurate results from use to use. REM The unit of measure of the equivalent absorbed dose in a human. Whole body For the purposes of external exposure determinations, include the head, trunk, gonads, legs above the knees, and arms above the elbows. III. Responsibilities A. Executive Manager 1. Support the RSO and AUs in complying with the requirements of this program. B. Radiation Safety Officer (RSO) 1. Calibrate or send the instruments for calibration. 2. Investigate the instrument's use for those instruments that fail the 'As Found' Data check during calibration. 3. Review the Dose reports. Page 2 of 22 Instrumentation and Dosimetry Program Rev. 2, 07/04/07 4. Co-ordinate the Quarterly exchange of personal monitoring devices. 5. Order and distribute personal monitoring devices. 6. Generate and send Individual Dose history as required or requested. 7. Maintain the records and documentation required by this program. C. All 1. Use the instruments in accordance with procedures and practices. 2. Wear personal monitoring devices as prescribed. 3. Notify the RSO of any problems with the instruments or dosimetry. 4. Update the Pre-operational Checks Sheets for the instruments. IV. Requirements for Instrumentation A. Multi-purpose Instruments 1. The Ludlum Model 3 with a G-M detector. a. Used in the areas with a need to monitor contamination and radiation levels. b. The x 0.1 scale is calibrated in cpm mode for contamination monitoring. c. Ranges - 0 - 420 cpm and 0 - 200 mR/hr d. Conversion rule 100 cpm = 1000 dpm 2. The Ludlum Model 14 C with a G-M detector. a. Used in the areas with a need to monitor contamination and radiation levels. b. The x 0.1 scale is calibrated in cpm mode for contamination monitoring. c. The x 1000 scale uses an internal probe. d. Ranges - 0 - 660 cpm and 0 - 2000 mR/hr e. Conversion rule 100 cpm = 1000 dpm B. Single-purpose Instruments 1. The Ludlum Model 14 B with a G-M detector. a. Used in the areas with a need to monitor radiation levels. b. Range - 0 – 2000 mR/hr 2. The Ludlum Model 12 with a proportional detector. a. Used in areas to monitor neutron radiation levels. b. Range - 0 – 500,000 cpm c. Conversion rule 75 cpm = 1 mREM/hr 3. The Ludlum Model 21 with a ZnS(Ag) probe. a. Used to count wipes for contamination. b. Range - 0 – 1,000,000 cpm 4. Packard 1600 TR Scintillation Counter a. Used to count prepared samples for contamination. b. Provides direct dpm results. c. Processes low energy at a minimum 60% efficiency, such as H-3 . Page 3 of 22 Instrumentation and Dosimetry Program Rev. 2, 07/04/07 5. Packard Cobra Gamma Counter a. Used to count prepared samples for contamination. b. Provides direct dpm results. C. Calibration 1. Calibrations will be conducted by, either a. A vendor licensed by the Nuclear Regulatory Commission, or b. Internal procedures reflective of and containing the requirements of the model instrument calibration program specified in Appendix O to NUREG-1556, Vol. 11, "Program - Specific Guidance about Licenses of Broad Scope." 2. Calibration Frequency a. Annually. b. Prior to initial use. c. Post maintenance evolutions that may effect the calibration. d. As requested by the RSO to verify proper operation. 3. Calibration failure of 'As found' data a. Investigate the use of the instrument. b. Conduct additional surveys, if possible and necessary, to verify previous instrument readings. c. Document the results of the investigation. 4. Calibration documentation a. Maintain the calibration records and applicable conversion charts for each instrument in accordance with the Administration Program procedures. D. Pre-operational Checks 1. Pre-operation checks provide the means to verify the instrument can reproduce accurate results from use to use. 2. Prior to use all instruments are source checked or verified to have been source checked in accordance with their use procedures. 3. The pre-operational checks include: a. A Calibration sticker verification to ensure the instrument has been and is currently calibrated. b. A battery/power check to ensure the instrument will have adequate voltage supplied to the detector and meter to reproduce readings. c. A source check to verify the instrument will give consistent readings to the same source from use to use and person to person. d. The documentation of the checks will provide validation of previous functionality during an investigation of an instrument failure. 4. The RSO will maintain a list of all instruments and their calibration due dates as a second check to ensure an uncalibrated instrument is not used. 5. Failure of pre-operational checks. a. The instrument is removed from service. b. The instrument is sent for recalibration. Page 4 of 22 Instrumentation and Dosimetry Program Rev. 2, 07/04/07 c. The RSO will investigate the use of the instrument. i. If the instrument 'As found' data is within the acceptable ranges, close out the investigation. ii. If the instrument 'As found' data is outside the acceptable ranges, the investigation will be completed under the calibration section. 6. Documentation of pre-operational checks. a. Pre-operational check records are kept with the instrument from calibration to calibration. b. Completed records are maintained in accordance with the Administration Program procedures. V. Requirements for Dosimetry A. Personal Monitoring Devices Shall Be Issued to: 1. Individuals expected to receive occupational exposure at levels > 10 mREM/month. 2. Individuals working with millicurie (mCi) quantities of , , , or X-Ray emitters. 3. Individuals involved with radioactive material or radiation producing machines, who request to be monitored due to personal concerns. B. Western Michigan University Will Use A Certified Supplier To Provide Dosimetry Services, Such As: 1. Calibration of dosimetry, 2. Routine and investigational readings, 3. Reports of individual exposure. C. Devices Worn For Establishing Record Dose Will Be Processed, Read, And Reported: 1. Quarterly, 2. As requested by the RSO. D. Table of Dose Limits Federal State WMU Level 2 WMU Level 1 Whole Body 5,000 1,250 100 50 mREM/yr mREM/qtr mREM/qtr mREM/qtr Lens of the Eye 15,000 1,250 1,000 500 mREM/yr mREM/qtr mREM/qtr mREM/qtr Skin 50,000 7,500 2,000 1,000 mREM/yr mREM/qtr mREM/qtr mREM/qtr Extremities 50,000 18,750 2,000 1,000 mREM/yr mREM/qtr mREM/qtr mREM/qtr Page 5 of 22 Instrumentation and Dosimetry Program Rev. 2, 07/04/07 Federal State WMU Level 2 WMU Level 1 Declared Pregnant 500 mREM/ 500 mREM/ Same as Same as Woman gestation gestation Above Above Minor (< 18 yrs) 10% of limits 10% of limits 75 N/A mREM/qtr Skin and Extremities 10% of limits 10% of limits 100 N/A mREM/qtr NOTE: For individuals exceeding WMU Level’s, follow the Emergency Plan for an Overexposure.